DAVIDSON
DAVIDSOX
tain, 2200 feet, and Bodya Head, 241 feet. In 1875
he visited the astrononiiovil observatories and
instrument worksliops of Europe, the field of the
great trignometrical survey of India, and of the
geodetic work of France, Prussia, Great Britain
and Switzerland. In 1878 he was sent to the
Paris exposition to examine instruments of pre-
cision in geodesy and astronomy and was elected
president of the jury of the moving powers of
machinery. As such he assisted in the exam-
ination of 3800 pieces of machinery and the
awarding of 8.j0 prizes, and received for these
services a medal and diploma from the French
government. In 1879 he made a second series of
observations between^ Round Top, 10,645 feet
above the sea and Jackson Butte, 2342 feet, and
in 1880 a third between Mt. Diabolo, 3849 feet, and
Martinez, 180 feet. In the development of the
main triangulation of the Pacific coast tlie lines
readied 192 miles, the longest yet reached in
geodetic work, 1879, and in 1892 he established
the intervisibility of the stations Mt. Diabolo,
8849 feet above the sea, and Mt. Shasta, 14,440
feet, the length of line being 244 miles. In 1880
he carried his large equatorial telescope to the
summit of Santa Lucia, 6000 feet, and observed
the total eclipse of January 11. This was the
only station at which this eclipse was observed.
In 1882 he had charge of the U.S. transit of
Venus expedition in New Mexico, 5500 feet above
the level of the sea, and in addition to instru-
mental observations, obtained 216 photograplis.
He was elected a meniber of the National acad-
emy of sciences in 1874, and of the principal
scientific societies of America and Europe at
various dates. He was president of the Cali-
fornia academy of sciences, 1871-86, and was
elected president of the "' Geographical society of
the Pacific " in 1881. He became honorary pro-
fessor of geodesy and astronomy in the Univer-
sity of California in 1870 and was a regent, 1877-
84. He was elected the first honorary member
of the San Francisco chamber of commerce for
"eminent public services " in 1889. In a single
period of nine years he presented seventy-three
prepared papers, besides innumerable notes and
diagi-ams, to the California academy of sciences.
In addition to his official and field duties, he as-
sisted in mapping the entire Pacific coast of the
United States, and determined the geographical
position of aU the prominent capes, bays and
lighthouses of the Pacific coast. In forty-five
years of active field service on the survey, he
travelled 382,000 miles and always with note-
book, instruments and sketchbook in hand. To
Jan. 1, 1898, his itinerary was 395,596 miles. In
1890 he had written over 2500 octavo pages of
geographical matter, illustrated by 530 views,
maps, etc. At his own expense he maintained
the first astronomical observatory on the Pacific
coast; and in 1873-74 largely influenced Mr.
James Lick in establishing the Lick observatory.
In 1891-92 he made, on every available night for
fifteen consecutive months, a series of observa-
tions for the determination of the ' ' Variation of
THE LICK observatory
Latitude," which demonstrated the 430 day period; and also gave a new determination of the "Constant of Aberration." In 1893 and 1894 he observed three other series for the varia- tion of latitude. In 1895 Professor Davidson was removed from his office after more than fifty years" service without a single charge against him, and representatives of influential societies and institutions throughout the country made a strong protest against the act, which was de- plored as weU by a number of foreign scientific societies as a great loss to geodetic science. In 1898 he accepted the professorship of geography in the new college of commerce established in the University of California. In 1889 ,he was U.S. delegate to the ninth conference of the Associa- tion Geodesique Internationale at Paris, and was by that body elected a member of the permanent commission. In 1894 he was nominated by the French ministry, and elected by the scientific members of the bureau of longitudes, the corre- sponding member to represent the United States. He was made an honorary member of the Amer- ican society of civil engineers in 1897 and an honorary corresponding member of the Royal geographical society in 1890. He was married in October, 1858, to Ellinor, daughter of Robert Henry Fauntleroy of Virginia. He received the honorary degree of Ph. D. from Santa Clara col- lege in 1876, and that of D.Sc. from the Univer- sity of Pennsylvania in 1889. His published works and papers on geodesy, astronomy, engi- neering and geography number over one hundred and thirty. He also published four editions of The Coast Pilot of California, Oref/on and Wash- ington (1858-62-69-88), the last edition embracing 720 quarto pages and 464 illustrations ; the Coast
